1. Field of the Invention
The present invention relates to a reader and a reader printer for enlarging and projecting the picture information photographed on a microfilm or microfiche.
2. Related Background Art
When a microfiche film is used as a microfilm for documents in a reader printer which has a horizontal type screen like a horizontal A4 format, since the documents have been photographed in a vertical format with regard to the film, and as in FIG. 14A, the projected image Fa is vertical to the horizontal screen 10 of A4 size with the portion Fa' remaining out of the screen surface, it is impossible to see the overall image of the document image Fa so long as the document image in a vertical format is enlarged by such a magnification as to make it substantially equal to the size of the horizontal screen to be projected on the screen.
Consequently, it is necessary to prepare two different lenses, one for a high magnification and the other for a low magnification, and through the changeover of the lenses in a turret, the document is first reduced so that the overall image may be projected on the A4 size screen, then when carrying out printing, the lens being changed over with the high magnification lens, the film carrier is rotated 90.degree., or otherwise the image is made sideways to be a horizontal A4 by a prism.
In the above mentioned conventional system wherein the high and low magnification lenses are prepared and changed over in a turret, however, the film carrier is forced to move at the time of the changeover. Furthermore, since it is necessary to rotate the image 90.degree. when printing, the operation to rotate the film carrier by 90.degree. has to be carried out.
Also when a prism is used for the high magnification lens in the turret, the film carrier is moved as well with the changeover of the lenses, and when correcting this, the correction of the image using the prism is necessary, therefore the positioning of the film carrier turns out troublesome.
Accordingly, it has been tried to add a prism to a zoom lens.
More particularly, the projection operation system is equipped with a zoom lens and a prism for the image rotation, and using the low magnification side of the zoom lens (the magnification to reduce the longer length of A4 to the shorter length of A4 for the projection), the overall image of the document image in a vertical format is reduced and projected Fb (reduction zooming) so that it may remain vertical within the range between the top and the bottom of the horizontal screen 10 to be read as illustrated in FIG. 14B.
Next when carrying out the printing of the document image, first the zoom lens is changed over to the high magnification side (the magnification to enlarge the document image to the A4 size: enlargement zooming), then the position of the projected image is rotated 90.degree. through the prism (90.degree. image rotation) so that the enlarged and horizontal image projected Fc may stay within the horizontal screen 10 as in FIG. 14C. After that by pressing the printing button, printing is carried out.
By the above mentioned system, however, the operation steps for the printing;
(1) zooming operation for enlargement (Fb+Fa) PA0 (2) 90.degree. image rotating operation PA0 (3) printing switch operation PA0 (4) zooming operation for reduction PA0 (5) 90.degree. image rotating operation (return rotation) turn out troublesome, since they must be carried out manually by an operator in this order (steps (1) and (2) as well as steps (4) and (5) may be carried out in the reverse order).
as well as the operations to read the next image after the printing;